West Ham have completed the signing of Manuel Lanzini on a four-year contract from Al Jazira. The 23-year-old midfielder had been on loan from the UAE club and has sealed a permanent switch to Upton Park.

The deal, which includes an option for a further two years, is understood to be worth around £9m.

Jack Sullivan, the son of West Ham’s joint-chairman David Sullivan, confirmed the news on Twitter. He wrote: “Lanzini is a WHU player for the next 4 seasons, with a further 2 year option.”

Slaven Bilic has now secured the futures of three of his key players after Dimitri Payet and Cheikhou Kouyaté recently signed long-term contracts.

Lanzini is back to full fitness following a spell on the sidelines with a thigh injury. The Argentinian scored his sixth goal of the season with a fine 20-yard curling shot in the 2-2 draw at Chelsea on Saturday.